Low temperature direct bonding of non-hydrophilicsurfaces

Oxidation and Induced Damage in Oxygen Plasma In Situ Wafer Bonding

“…2 For the majority of DWB applications it is clearly of importance that a well-adhered, high-quality interface can be achieved at low temperatures. Several authors [3][4][5][6] propose activation with oxygen plasmas prior to bonding as one way of achieving this. In all these reported experiments, wafers were brought out of the plasma chambers and contacted in ambient air.…”

Chemical role of oxygen plasma in wafer bonding using borosilicate glasses

“…4 -8 The role of the prebonding O 2 plasma treatment has been suggested to include the introduction of a surface charge, 4 the removal of hydrocarbons by etching of the surface, 6 or the creation of a damaged oxide with unsatisfied surface SiO x bonds that is said to be ''activated.'' 5,7 In this research, the goal is to probe the chemical changes induced by the O 2 plasma treatment and DI H 2 O rinse using Fourier transform infrared spectroscopy ͑FTIR͒. First, changes in the oxide layer were monitored by tracking the Si-O and B-O vibrations after each processing step.…”

“…3 A hydrophilic oxide surface for wafer bonding can be prepared by either wet chemical treatments or by dry plasma treatments. [3][4][5][6][7] A common prebonding treatment that is being investigated as a means of forming strong room temperature bonds is exposure of the surface to an O 2 plasma followed by a DI H 2 O rinse. Previous studies have indicated that this prebonding treatment results in strong bonding between Si and SiO 2 /Si surfaces and GaAs and borosilicate glass ͑BSG͒/GaAs surfaces.…”